CUBASE AND MOXF ISSUES

Hello. I need help. I,m trying to use my MOXF with CUBASE. But now, every time i create a MIDI track i have issues. A “Transmitting MIDI bulk” message appears in the MOXF and it won´t stop until i turn off the keyboard. Sometimes i can create the MIDI track, i can record but i am not able to hear what i´ve recorded. I´ve tried to create an instrument track with MOXF as a VST but the connection was impossible or the ports didn´t function.
But the worst problem is that i found no logic in all these issues. I did some recordings. It was really a nightmare but somehow i managed to configure the program an record some songs. While i had no problems working with Apple Logic Pro (and i still have NO problems with MOXF ports in Logic) in Cubase everything seems to be unstable.
I followed all the instructions from Steinberg and Yamaha but i was not able to find the solution.
PS: When i was able to record with my MOXF as a VST INSTRUMENT in CUBASE, i only was able to do it with a single track. As soon as i opened another VST track i had port problems. It would be a dream to have 5 or 6 MOXF VST TRACKS assigned to different midi channels and then doing the audio mix down. ¿Is this possible?
Thanks in advance